Perhaps you should try some spelling variations:
doc sach » hoc sach, toc sach, nuoc sach
hieu van » hieu va, thien van, lieu va
luoc can » luc canh, hoc can, luoc dai
can hanh » ban hanh, van hanh, dan hanh
te sach » toc sach
van tom » van tam, van toi, van toa
keo cua » keo sua, khoe cua, cheo cua
kho cua » khoe cua, khi cua, cho cua
x hoi » xa hoi, o hoi, x ho

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) or (doc sach)) ky nang x hoi. hieu van tom luoc can hanh ((keo cua) OR (kho cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (doc sach)) ky nang x hoi. hieu van tom luoc can hanh ((keo cua) OR (kho cua)) te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (doc sach)) ky nang x hoi. hieu van tom luoc can hanh ((keo cua) OR (kho cua)) te".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (doc sach)) ky nang x hoi. hieu van tom luoc can hanh ((keo cua) OR (kho cua)) te*.